Unfortunately, the new SimCity game (2013) is being built to be 100%
online with a focus on multiplayer mode.The single player mode announced by Maxis is not a real single or solo
player mode, and it will be only online. This will have limitations that don’t exist in the multiplayer
mode.Even if you playing alone in the new SimCity (2013), your game will be
influenced by other players indirectly through a worldwide network of players in
the EA Servers with leaderboards and other external influences.You may even be penalized if you want to play alone in the new game or don’t
have access to certain features of the game to force you to move to the multiplayer
mode.Member of the Simtropolis forum, SoftcoreGamer says:- MULTI-PLAY THE FOCUS; SINGLE PLAYERS WILL BE PENALIZED: play ground
and be blocked from "great works" which only multi-players get to
build. Great works are large scale projects such as intl airport, which will
earn extra in-game rewards for multi-players being obedient Maxis drones. For
example, single-play tourist city will suffer tourist inflow stagnation because
sorry, international airport is unavailable to single players.http://www.gameinformer.com/games/simcity/b/pc/archive/2012/07/06/interview-a-new-multiplayer-focus.aspx?PageIndex=1http://www.gameinformer.com/games/simcity/b/pc/archive/2012/07/06/interview-a-new-multiplayer-focus.aspx?PageIndex=2

Mkareha: Will there be terraforming in the sense of a "god
mode" like there was in SimCity 4?

Creative Director Ocean Quigley: No,
all of the terraforming in this SimCity
is going to be at the civil engineering scale, and will be the natural consequences
of laying out roads, developing zones, and plopping buildings.

8) Road connections placed
in a fixed and pre-determined location in the map.

neil5280 wrote:

I was able to play SimCity and speak with Community Manager Michael quite a bit, at PAX.
[...]. The roads issue became frustrating when you play near the
freeway that goes between cities. In the pre-alpha software your
connection point to the highway is pre-determined, which means if you
are planning a city, you can't just put your main arterial anywhere.
Additionally, it's quite annoying to be able to build so close to the
freeway without being able to make arbitrary connections to it, or run
roads under it to develop on the other side. [...]

I have two questions:
1. Could you tell something about the maximum size of a city? Will it be
the same scale as a massive city in 3 & 4, or should we expect
final cities to be a bit smaller because of the new Glassbox engine?
2. What do you think will be the biggest gameplay improvement over
SimCity 4?

Maxis:

[Dan] The size of our new cities are roughly equivalent to the SC4
medium sized city (2 kilometers square).